Mortising machine work holding attachment to drill press



Nov. 27, 1951 H v. SCHWANDT 2,576,485

MORTISINC MACHINE WORK HOLDING ATTACHMENT TO DRILL PRESSES Filed April 2, 1948 .Haward HSchwaWdZ Patented Nov. 27, 1951 UNITED STATES PATENT OFFICE MOB/TISING MACHINE WORK HOLDING ATTACHMENT T DRILL PRESS 3 Claims.

This invention relates to mortising machines, and more particularly to an improved mortising attachment for use with drill presses.

Mortising tools comprising a, rotary bit, 2. rectangular chisel surrounding the bit and achisel holder have been used in conventional drill presses for cutting openings in the edges of doors, windows, and the like to receive looking or other devices adapted to be mounted in such openings. Where conventional fences or stops are used to position the door'or the like to be mortised, the fences or stops must be carefully adjusted to properly align the work with the mortising chisel, so that the mortise cut will be made at the desired location properly spaced from the edges or faces of the work being mortised. This invention provides a simple attachment for drill presses to position and hold the work in the correct alignment for mortising, regardless of the thickness of the work, and regardless of whether the mortise is to be centered or off-centered in the thickness of the work.

It is an object of this inventionto provide an improved work-holding attachment for drill presses to properly position and hold work to be mortised or drilled.

It is another object of this invention to provide an attachment of the character described which may be easily mounted on the conventional drill press.

It is another object of this invention to provide a mortising attachment for drill presses which will positively grip and hold work of various thicknesses and automatically align successive work pieces under a mortising tool.

It is a further object of this invention to provide a mortising attachment for drill presses which permits the work to be mortised to be easily mounted in or removed from the press and which securely holds the work while the mortising tool is withdrawn from the work.

It is still another object of this invention to provide for drill presses a mortising attachment which may be easily and economically constructed, and which may be easily swung to one side when it is desired to use the press for conventional drilling operations.

Numerous other objects and advantages of the invention will be readily apparent to those skilled in the art from the following detailed description of a preferred embodiment of the invention illustrated in the accompanying drawings, wherein:

Figure 1 is a side elevatlonal view of a drill press partly cut away and equipped with a mortising attachment having a door positioned therein for mortising.

Figure 2 is an enlarged elevational view of the mortising attachment from the opposite side of the view illustrated in Figure 1.

Figure 3 is an elevational view partly in section of the outer jaw mounting of the mortising attachment shown in Figure 2.

Figure 4 is an elevational view partly in sec.- tion taken on line 4-4 of Figure 3 and showing in dotted lines the raised position of the outer jaw member.

Referring to Figure 1 of the drawings, for the purposes of illustration, the drill press is provided with a base I 0 supporting an upright standard or rigid post II. The press head I2 is rigidly secured to the top of the post I l and includes a driving motor l3 geared or belted to the drill spindle I4 in conventional manner. The drill spindle I4 is mounted in the head l2 for vertical movement and a manually-operated lever I5 is provided for shifting the drill spindle I4 downward and upward. 7

An adjustable work table or work support I6 is provided on the lower portion of the post H and may be rigidly clamped to the post at the desired height by means of clamp H. A suitable work positioning fence or stop I 8 may be adjustably secured to the upper surface of support It.

The drill spindle I4 is provided with a mortising tool when the drill press is to be used for mortising operations, the tool being secured in the usual drill chuck l9 and including a drill bit, not shown, enclosed Within a hollow rectangular chisel 20 held by a chisel holder 2 l, the latter being clamped to a non-rotating sleeve around the drill spindle and movable vertically with the spindle.

The mortising attachment of this invention includes a support member '25 slidable on the post i l and rigidly clamped at the desired height thereon by a tightening lever 26. Extending horizontally forward from and rigidly secured to the support 25 is a bar or rod 21. One or more rods 21 may be provided, and the rod 2'! may be of circular crosssection, as shown in Figure 4, or may be of square or other cross-section. Slideably supported on the rods 21 are jaw supporting arms 28 to which the downwardly projecting jaw portion 30 is rigidly secured for engagement with the rear side of the work to be mortised. A threaded rod 32 extends horizontally forward from the support 25 to which it is journaled in a thrust bearing 33. The rod 32 is provided with screw threads, the threads 34 of one portion being of opposite pitch to the pitch of the other portion 35, and may be provided with a central supporting bearing 330. at the forward portion of member 25. The upper portion of one of the arms 28 (Figure 2) is provided with a threaded bushing 36 engaging the threaded portion 34 of rod 32. A hand crank 38 is secured to the rearward end of rod 32 for rotating the same. The outer jaw 3| is pivotally carried by the member 29 which is supported for horizontal adjustment on the projecting portion of one of the bars 21. The downwardly extending jaw 3| is provided with a collar portion 45 mounted for rotation on a hub 39 projecting from the member 29, and is secured thereon by a locked nut or spring washer 48. A spring finger 4| may be secured to the member 29 by a bolt 42, and is provided at its outer free end with a ball 43 which engages suitable recesses 44 in the periphery of the collar portion 45 of jaw 3|. The jaw 3| may thus be turned or swung on the hub 39 from the downward position, as shown in Figures 1, 3, and 4 to a horizontal position 3| indicated in dotted lines in Figure 4 to permit the work to be easily inserted in or withdrawn from the attachment, The spring detent 43 serves to hold the jaw 3| in either position. The upper portion of member 29 is provided with a threaded bushing 31 extending therethrough, there being a set screw 38 provided to lock the bushing 31 to member 29. An adjusting wheel 31a is provided on the outer end of bushing 31 to permit the bushing to be conveniently turned after the set screw 38 is loosened. A work engaging member 5'6 is adjustably secured to the outer face of the bracket and is provided with one or more fingers 41 projecting horizontally forward over the upper edge of the work 48 to prevent the latter from being lifted off the support It when the mortising chisel 28 is withdrawn from the Work.

The operation of the mortising attachment will now be described. The work support It is positioned on the post I I so that when the lower edge of the work to be mortised, such as the door 48 shown in Figure l, is positioned on the support [6 against the stop or fence |8, the upper edge of the door will be below the upper position of the mortising chisel 20. The attachment support member 25 is rigidly secured to the post i so that the rod 21 and the threaded rod 32 are above the door edge to be mortised and the member 46 is adjusted to engage the upper edge of the work 48. The jaw 3| may be swung up to the horizontal position while the work 48 is placed in position, and may then be turned downward to the position illustrated in Figure 1. The hand crank 38 is then turned to rotate the threaded rod 32 to slide the members 28 and 29 toward each other along the supporting rod 21 by means of the right-hand and left-hand threads 34 and 35. As the jaws 38 and 3| are moved toward each other, they grip the sides of the work 48 and automatically align the upper edge of the work under the mortising chisel 20. The threads 34 and being of equal pitch in opposite directions, the work 58 is always properly clamped and aligned under the mortising tool. The lever I5 is operated to advance the mortising tool 28 into the Work and after the mor-' tise is cut, the tool is withdrawn from the work by the same lever. The fingers 41 of the member 46 prevent the work from being raised when the tool is withdrawn. The crank 38 is then turned to release the jaws 23 and '29 from the work 48, jaw 3| is turned to its upper position shown in dotted lines in Figure 4, and the work may be easily removed from the press. The next work piece may then be inserted in the press for mortising. Where the mortise to be cut is not to be 4 centered in the thickness of the work 48, the member 29 may be adjusted along the rod 32 by loosening the set screw 38 and then turning the wheel 31a. The set screw 38 is then tightened and the attachment is ready for properly aligning successive work pieces for mortising.

It will be apparent that the mortising attachment serves to quickly align and hold successive work pieces to be mortised. No separate adjustments need be made for mortising successive pieces of different thickness since the attachment correctly aligns each work piece regardless of its thickness. The pivotally mounted jaw 3| permits work to be quickly placed in or removed from the mortising position. This feature is of great advantage where a press provided with the illustrated attachment is used in building construction work at the building site. Doors and other pieces of various sizes and thicknesses may be quickly mortised in minimum time. While the attachment illustrated herein has been described for use in mortising operations only, it will be readily apparent that its use is not restricted to mortising, and that it will be equally advantageous in drilling or other operations performed by drill presses, where it is desired to quickly position and clamp the work to be drilled or cut. Where it is required that the cutting operation be effected not at the center of the edge thickness of the work piece, the wheel 3101. may be adjusted to offset the work from being centered under the tool. It is also to be understood that various constructions other than the spring detent 43 may be provided for holding the pivoted jaw 3| in the upper and lower positions. By loosening the lever 25, the support 25 carrying the entire mortising attachment may be swung to one side to clear the drill press for conventional drilling operations.

Obviously many other variations in the nature and arrangement of the various elements illustrated and described will be readily evident to those skilled in this art, and this invention contemplates any such equivalent structures within the scope of the following claims.

I claim:

1. A mortising attachment for positioning and holding work to be mortised in a drill press, comprising in combination, a support securable to a rigid portion of said drill press, a rod secured to and extending horizontally forward from said support over the top edge of work to be mortised, a jaw-supporting member slidable on said rod, a clamping jaw carried by said member and depending below the axis of said horizontal rod, a,

second jaw-supporting member slidable on said rod, a clamping jaw pivotally carried by said second member, and adjustable threaded means engaging both of said jaw-supporting members for sliding said clamping jaws toward each other simultaneously into engagement with the sides of work below said horizontal rod, said pivotallycarried depending jaw being swingable on a horizontal axis to a position above the top edge of the work to facilitate the entry and removal of work to and from said positioning jaws.

2. A mortising attachment as set forth in claim 1, said support having a clamping member secured to and extending horizontally forward from said support below the horizontal axis of said rod for engagement with the upper edge of the the work to be mortised.

3. A mortising attachment as set forth in claim 1, said second jaw-supporting member being provided with a rotatable bushing threaded to said REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Bretland June 24, 1890 Number Number 6 Name Date Williamson Jan. 19, 1897 Ensign Apr. 28, 1903 Felton Apr. 26, 1921 Rigert July 25, 1922 Halvorsen et a1. Aug. 18, 1930 Dewey Sept. 10, 1940 Mead Jan. 13, 1942 Wetzler Nov. 18, 1947 

